Altered chords are a great spice to add to any song, especially in Jazz and Fusion. But trying to improvise over them in a solo can be disastrous if you aren't playing on the key tones of the chord, you will just create a large amount of a-tonal and diminished notes that you might not want in your lines. In this great video you will learn one great technique to keep in mind when improvising a solo over an altered chord using melodic minor of the note a half step up from the root of the altered chord.